Improvement in dovetailing-machines



UNITED STATES PATENT SAMUEL E. HARTWELL, OF NEW ALBANY, INDIANA.

IMPROVEMENT IN DOVETAlLlNG-MACHINES.

Specification forming part of Letters Patent No. 41,992, dated March 22,1864.

To all whom, it may concern:

`thereof, reference being had to the accompanying drawings, making partof this specification.

My invention relates to a provision for cutting a complete set ofdovetail tenons and corresponding mortises on the parts ofa drawer, box,or the like.

Figure 1 is a perspective View of a machine embodying my invention. Fig.2 shows a cutter and mandrel to full size. Fig. 3 is an end view of thesame. Fig. 4 is a longitudinal section of a portion of the machine.Figs. 5, 6, 7, and 8 are diagrams illustrating the dovetailin g actionof my cutters on the work.

Journa-led vertically and' equidistant in a fra-me, A, is a gang ofmandrels, B, surmounted by conical cutterheads, C, which are adjusted toan exactly corresponding elevation by means of slots, d, in the steps Dand boxes D.

As arranged in Figs. 1, 5, and 6, the cutters are adapted to form thetenons l and mortises 2 of exactly equal dimensions. This is, however,not imperative, as two distinct sets of cutters, 3 and 4, may beemployed, respectively, for the tenons 6 and mortises 5, (see Figs. 7and 8;) but whether of equal or unequal size tlle cutters have the sameangular contour, and are arranged at equal distances from center tocenter in the gang.

The operative portion of each cutter consists of two opposite blades, KK', which terminate in pods or lips 7c k. The cuttingedge 9 l0 of eachblade, K or K', is so formed as to project forward of a radial positionfrom heel 9 to point 1.0, so as to enable the lip K or K and point 10 toinitiate the cutting action and cause the cutter to hug the work to thebed, and to operate with a paring or shaving rather than with a breakingand tearing action, resulting in great economy of power, and imparting asmooth and even iinish to the bottom andsides of the mortises and sharpunbroken angles to the tenons.

The work is supported and guided lto the cutters by a sliding bed, E,which bed is restricted to a motion at right angles to the gang ofcutters by guides F in the frame A. e is a stop to limit the stroke ofthe bed.

G is an adjustable gage, against which the edge of the stuff is pressedwhen about to be forwarded to the cutters.

H is a clamp for holding the end piece of av drawer or box down to bemortised.

brought down to the position represented in` Fig. 4, in which figure thered lines indicate the stuit' held securely in position by means of`set-screws J.

In the above-described illustration of my invention a gang of ve bits isemployed, but it is evident a greater or less number may be used withoutdeparting from my plan.

I claim herein as new and of myinventionl. The arrangement of the gangof conical dovetailing-bits C K K k 7c', rotating on axes at rightangles to the plane of motion of the bed E, substantially as and for theexplained.

2. The combination of the adjustable dovetailing-bits C K K 7c k bed Ee, sliding in a plane at right angles to the axes oi' the said bits, theclamps H and I, and gage G, the whole being arranged and operatingsubstantially as set fort a. The dovemningeutter c K xl 1. 1.-',

operated as represented in the foregoing specication.

1n testimony of which invention, I hereunto set hand.

S. E. HARTWELL. Witnesses:

GEO. H. KNIGHT, PH. F. BALDAUEF.

purposes

